Lexmark Optra S 4059 Series, Service Manual

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4059 Service Manual
4059-XXX
Duplex Option
The duplex option interface is a six pin autoconnector that provides a
+24 V dc, +24 V dc return, serial interface transmit signal, serial
interface receive signal and two ground pins. The duplex option
receives the +24 V dc from the base printer for the duplex motors
and also converts the voltage to +5 V dc for duplex electronics.
Duplex chassis grounding is provided from the printer to the duplex
option through a ground spring attached to the frame and base of
the printer. The ground connection is automatically made when the
option is installed below the printer.
The paper input sensor is located in the rear of the duplex unit under
the input paper guide. The rear cover open switch is located on the
rear cover assembly. The paper exit sensor is located on the left
frame assembly. The jam removal tray open switch is located at the
end of the left frame assembly. There are no switches in the level 2
duplex option.
Option Microcode
The options are “Smart Options” or options that have a system
board. The option system board has a microprocessor that controls
the option mechanism. A software architecture is provided that
controls the option and communicates information such as paper
path status, sensor or switch status, motor status and so on to the
base printer.
Fuser Operation
The fuser in the Optra S printers is made up of two primary
assemblies. The first assembly is the top fuser cover which contains
the thermistor/cable, thermal fuse, cable assembly, left and right
lamp brackets and cover. This is a complete assembly and the parts
cannot be individually replaced as in previous Lexmark laser
printers.
The thermal fuse protects the fuser assembly from overheating or
problems with the fuser lamp by opening the ac circuit to the lamp.
The thermistor assembly is designed to keep the temperature of the
fuser hot roll within a predetermined temperature by being in contact
with the fuser hot roll and changes resistance as the temperature of